The present invention relates to vehicle seats and particularly to seat backrests of the type which include internal structures for selectively adjusting the seat cushion contour to provide varying degrees of lumbar support to a seat occupant.
The desirability for providing support for the lumbar region of the back of a seat occupant has long been recognized and various patents, including U.S. Pat. Nos. 3,807,794; 3,890,000; 3,948,558 and 3,973,797 disclose structures for permitting a fore and aft adjustment of an internal lumbar pad within a back cushion.